DOI: 10.1111/1471-0528.12754
General obstetrics
www.bjog.org
Gestational diabetes mellitus and later cardiovascular disease: a Swedish population based case–control study ¨ stlund,a S Montgomery,b,c U Hanson,a,d E Schwarcze H Fadl,a A Magnuson,b I O ¨ rebro University, O ¨ rebro, Sweden b Clinical Department of Obstetrics and Gynaecology, School of Health and Medical Sciences, O ¨ ¨ ¨ rebro, Sweden Epidemiology and Biostatistics, Orebro University Hospital, School of Medical Health and Sciences, Orebro University, O c Clinical Epidemiology Unit, Karolinska Institutet, Stockholm, Sweden d Department of Women’s and Children’s Health, Uppsala University, ¨ rebro University, O ¨ rebro, Sweden Uppsala, Sweden e Department of Internal Medicine, School of Health and Medical Sciences, O ¨ rebro University Hospital, SE 70185 O ¨ rebro, Sweden. Correspondence: H Fadl, Department of Obstetrics and Gynaecology, O Email [email protected] a
Accepted 20 December 2013. Published Online 25 April 2014.
Objective To identify if gestational diabetes mellitus (GDM) is a
clinically useful marker of future cardiovascular disease (CVD) risk and if GDM combined with other risks (smoking, hypertension or body mass) identifies high-risk groups. Design Population-based matched case–control study. Setting National Swedish register data from 1991 to 2008. Population A total of 2639 women with a cardiovascular event
and matched controls. Methods Conditional logistic regression examined associations with
CVD before and after adjustment for conventional risk factors and confounders. Effect modification for the association of GDM with CVD by body mass index (BMI), smoking and chronic hypertension was assessed by stratification and interaction testing. Adjustment for diabetes post-pregnancy evaluated its mediating role. Main outcome measures Inpatient diagnoses or causes of death
identifying ischemic heart disease, ischemic stroke, atherosclerosis or peripheral vascular disease.
Results The adjusted odds ratios (and 95% confidence intervals) for the association of CVD with GDM are 1.51 (1.07–2.14), 2.23 (2.01–2.48) for smoking, 1.98 (1.71–2.29) for obesity and 5.10 (3.18–8.18) for chronic hypertension. In stratified analysis the association of CVD with GDM was only seen among women with BMI ≥25, with an odds ratio of 2.39 (1.39–4.10), but only women with a BMI 25, 42.0% versus 30.3%), parity (mean 2.44, SD 1.2 versus 2.62, SD 1.2), lower education level (I/ II, 23.4% versus 15.1%) and non-Nordic origin (14.2% versus 11.4%) (Table 1). Associations with cardiovascular disease for GDM and other characteristics are presented in Table 1. Chronic hypertension, smoking, GDM, parity, BMI and lower education were notably associated with CVD events. After adjustment for chronic hypertension, GDM, smoking, BMI, education level, parity and ethnicity, respectively, all factors were statistically significantly associated with an increased risk of CVD events. The unadjusted odds ratio (and 95% confidence interval) for the association of GDM with cardiovascular disease was 2.19 (95% CI 1.59–3.01) and 1.51 (95% CI 1.07–2.14) after adjustment. Table 1 demonstrates that hypertensive diseases
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and smoking during pregnancy have higher magnitude associations with cardiovascular disease than GDM. Stratification by BMI indicated that GDM was statistically significantly associated with CVD among overweight women, but not among normal weight women (Table 2). For women with BMI ≥ 25 the odds ratio for the association of GDM with CVD was 2.23 (95% CI 1.38–3.62) before adjustment and 2.39 (95% CI 1.39–4.10) after adjustment, but only women with a BMI
General obstetrics
www.bjog.org
Gestational diabetes mellitus and later cardiovascular disease: a Swedish population based case–control study ¨ stlund,a S Montgomery,b,c U Hanson,a,d E Schwarcze H Fadl,a A Magnuson,b I O ¨ rebro University, O ¨ rebro, Sweden b Clinical Department of Obstetrics and Gynaecology, School of Health and Medical Sciences, O ¨ ¨ ¨ rebro, Sweden Epidemiology and Biostatistics, Orebro University Hospital, School of Medical Health and Sciences, Orebro University, O c Clinical Epidemiology Unit, Karolinska Institutet, Stockholm, Sweden d Department of Women’s and Children’s Health, Uppsala University, ¨ rebro University, O ¨ rebro, Sweden Uppsala, Sweden e Department of Internal Medicine, School of Health and Medical Sciences, O ¨ rebro University Hospital, SE 70185 O ¨ rebro, Sweden. Correspondence: H Fadl, Department of Obstetrics and Gynaecology, O Email [email protected] a
Accepted 20 December 2013. Published Online 25 April 2014.
Objective To identify if gestational diabetes mellitus (GDM) is a
clinically useful marker of future cardiovascular disease (CVD) risk and if GDM combined with other risks (smoking, hypertension or body mass) identifies high-risk groups. Design Population-based matched case–control study. Setting National Swedish register data from 1991 to 2008. Population A total of 2639 women with a cardiovascular event
and matched controls. Methods Conditional logistic regression examined associations with
CVD before and after adjustment for conventional risk factors and confounders. Effect modification for the association of GDM with CVD by body mass index (BMI), smoking and chronic hypertension was assessed by stratification and interaction testing. Adjustment for diabetes post-pregnancy evaluated its mediating role. Main outcome measures Inpatient diagnoses or causes of death
identifying ischemic heart disease, ischemic stroke, atherosclerosis or peripheral vascular disease.
Results The adjusted odds ratios (and 95% confidence intervals) for the association of CVD with GDM are 1.51 (1.07–2.14), 2.23 (2.01–2.48) for smoking, 1.98 (1.71–2.29) for obesity and 5.10 (3.18–8.18) for chronic hypertension. In stratified analysis the association of CVD with GDM was only seen among women with BMI ≥25, with an odds ratio of 2.39 (1.39–4.10), but only women with a BMI 25, 42.0% versus 30.3%), parity (mean 2.44, SD 1.2 versus 2.62, SD 1.2), lower education level (I/ II, 23.4% versus 15.1%) and non-Nordic origin (14.2% versus 11.4%) (Table 1). Associations with cardiovascular disease for GDM and other characteristics are presented in Table 1. Chronic hypertension, smoking, GDM, parity, BMI and lower education were notably associated with CVD events. After adjustment for chronic hypertension, GDM, smoking, BMI, education level, parity and ethnicity, respectively, all factors were statistically significantly associated with an increased risk of CVD events. The unadjusted odds ratio (and 95% confidence interval) for the association of GDM with cardiovascular disease was 2.19 (95% CI 1.59–3.01) and 1.51 (95% CI 1.07–2.14) after adjustment. Table 1 demonstrates that hypertensive diseases
1532
and smoking during pregnancy have higher magnitude associations with cardiovascular disease than GDM. Stratification by BMI indicated that GDM was statistically significantly associated with CVD among overweight women, but not among normal weight women (Table 2). For women with BMI ≥ 25 the odds ratio for the association of GDM with CVD was 2.23 (95% CI 1.38–3.62) before adjustment and 2.39 (95% CI 1.39–4.10) after adjustment, but only women with a BMI
